The ins and outs of how to care for a dog suffering from stones.
A bladder stone, or urolith, develops when mineral salts in urine combine and harden. Most stones occur in the bladder and urethra, but occasionally stones form in the kidneys and ureters, the tubes that carry urine from the kidneys to the bladder. Dogs may develop one or more large or small stones. The five main types of stones that affect pets are struvite, calcium oxalate, urate, cystine, and silicate.
Risk Factors and Detection
Bladder stones affect dogs any age and breed, but certain stones tend to affect specific breeds.
Female dogs with urinary tract infections can develop struvite stones. Other risk factors include medications or metabolic diseases that cause increased mineral-salt concentrations in the urine. Urine retention and anatomic abnormalities of the bladder also could contribute to bladder stone formation.
Signs of a bladder stone include the following:
These last three signs may indicate a bladder stone is completely obstructing urine flow. This condition is life-threatening, so take your dog to the veterinarian immediately.
Your veterinarian will perform a complete physical examination and may use blood tests, X-rays, ultrasound, urinalysis, bacterial culture and sensitivity testing, and stone analysis to diagnose the presence and type of bladder stone, as well as any underlying metabolic disease. If your dog passes a stone while urinating, save it. Your veterinarian will have its mineral content analyzed before choosing a treatment.
Prevention and Treatment
Fresh water, frequent bathroom breaks, and avoiding obesity reduces your dogs risk of bladder stone development. If your pet develops a urinary tract infection, seek veterinary care and complete all antibiotic treatments.
When treating bladder stones, your veterinarians goals are to relieve any urinary obstruction, treat any infection, and dissolve or remove the stones. To remove a blockage, your veterinarian may use a urinary catheter or a cystoscope, a special scope designed for evaluating the bladder. Other treatments include surgery or urohydropropulsion, in which your veterinarian uses a catheter and fluid to flush out the stone. If the obstruction causes other illness, such as metabolic abnormalities, your dog may need intravenous fluids and hospitalization.
Different types of bladder stones require different treatments. Struvite, urate, and cystine stones respond well to medical dissolution. Depending on the type of stone, your veterinarian may use a special diet and possibly medication to dissolve it. The goals of this treatment are to decrease the concentration of stone-forming salts in the urine, increase the solubility of those salts by altering the urines pH, and increase urine volume.
Calcium oxalate and silicate stones are harder to treat and often require surgery. Your dog also may need surgery to relieve an obstruction, to remove stones that dont respond to medical dissolution, or to correct anatomic abnormalities of the bladder that contribute to stone formation. Veterinarians prefer surgery when medical dissolution is inadvisable because of other medical conditions.
Dissolving bladder stones with a special diet can take a few weeks to a few months. During this time, dont vary your dogs diet, or treatment will be ineffective. Your pet will need follow-up urinalyses, bacterial cultures, and X-rays to ensure complete dissolution. Bladder stones are likelier to recur in pets with metabolic disorders or a hereditary predisposition. But in many cases, special diets and medications that alter urine acidity can prevent recurrence.
Pets who undergo surgery generally recover without problems, but they also require preventive care to halt recurrence.